A narrow opening or groove into which something can fit, such as a coin slot in a machine or the opening in a car seat belt where it fits. Also, the term for a time slot on a calendar or scheduling tool, where events or meetings can be scheduled at specified times throughout a week.

In gambling, a slot is a spinning reel that pays out credits when certain symbols line up on the payline. The amount of credits won depends on the type of slot and how much is wagered. Some slots offer different bonus rounds and additional symbols that can increase the amount won.

With the advent of electronic slot machines, manufacturers have been able to adjust the odds of specific symbols appearing on a payline in order to maximize profits. They do this by changing the frequency of symbols that appear on a given reel, or by altering the number of stops on a physical reel.

In modern video slots, the probability of winning is determined by a mathematical formula that takes into account how often each symbol appears on a reel and how frequently it must be hit to trigger a prize. This information is compiled by the slot machine manufacturer and provided to players in a help menu. Some casinos also provide an RTP, or return to player percentage, which indicates the average amount of money a slot machine returns to its players. A slot’s volatility, or risk/reward ratio, is also an important consideration when choosing a game to play. A low volatility slot will pay out often but with smaller wins, while a high volatility slot may only payout rarely, but when it does, the amounts will be large.